In computer networking and telecommunications, Multi Protocol Label Switching (MPLS) is a known data-carrying mechanism that belongs to the family of packet-switched networks. MPLS operates at an Open Systems Interconnection (OSI) Model layer that is generally considered to lie between traditional definitions of Layer 2 (Data Link Layer) and Layer 3 (Network Layer), and is therefore commonly referred to as a “Layer 2.5” protocol. MPLS can be used to carry many different kinds of traffic, including IP packets, as well as native ATM, SONET, and Ethernet frames.
MPLS Traffic Engineering (MPLS TE) is the process of selecting and reserving a path between the nodes so as to optimize the network resources, in order to provide improved bandwidth utilization and Quality of Service (QoS). Thus, traffic Engineering (TE) is particularly important for service provider backbones, and where there are single or multiple paths (tunnels) in a network for the transmission of packets. Such tunnels are typically configured by the network administrator.
The path of a tunnel is a crucial factor which affects the tunnel performance and status. For certain types of tunnels starting from network devices, path information may not be complete or available. Consequently, a network operator or administrator will have a limited insight into the tunnel route through the various network nodes and, thus, cannot accurately determine the source(s) of potential problems. Also, since tunnel path information is important for monitoring tunnel health, network management is made less accurate and more difficult.